Great, if a little impenetrable - UPDATE
Update April 2024 - I still think this is a great problem-solver. I used it for interfacing a keyboard which sends too many CCs to external gear, and I could block some messages and transform others to what I wanted. The example presets contain all of the techniques I needed (with some adaptation).
Amazing
Also... its free!?!?
Not just great fun, but...
Especially if one likes a little haphazard musical generation.
6.8mb of adulterated MIDI streams!